The Merriam-Webster dictionary defines a davit as a crane that projects over the side of a ship or a hatchway and is used especially for boats, anchors, or cargo.
In most davit systems, a winch or similar device uncoils a plurality of cables that extend to a boat or other structure to be lifted. The free ends of the cables are secured to the structure to be lifted and then the winch is operated in an opposite direction to retract the cables and thus lift the structure. In most designs, a cantilever construction is employed so that the cables can reach out whatever distance is needed to reach a operative position over the structure to be lifted.
The stress that appears on a davit system is therefore quite high. The downwardly directed force appearing on the distal free ends of each cantilevered arm during a lifting operation is of course multiplied by the length of the arm. As a result, conventional davit systems are built for strength. This increases their weight and their manufacturing expense.
What is needed, then, is a davit system that is under less stress when operating than a typical, cantilevered davit system. Such a davit system could be manufactured at a lower cost than the high strength davit systems that are currently in widespread use.
However, in view of the prior art taken as a whole at the time the present invention was made, it was not obvious to those of ordinary skill how the identified need for an improved davit system could be fulfilled.